Halopenitus malekzadehii sp. nov., an extremely halophilic archaeon isolated from a salt lake

Abstract

Strain CC65T, a novel extremely halophilic archaeon, was isolated from a brine sample of a salt lake in Iran. The novel strain was light yellow-pigmented, non-motile, pleomorphic and required at least 1.7 M NaCl and 0.02 M MgCl2 for growth. Optimal growth was achieved at 3.5 M NaCl and 0.4 M MgCl2. The optimum pH and temperature for growth were pH 7.5 and 40 °C, respectively, while it was able to grow over a pH and a temperature range of pH 6.5–9.0 and 30–50 °C, respectively. Analysis of 16S rRNA gene sequence revealed that strain CC65T clustered with the sole member of the genus Halopenitus , Halopenitus persicus DC30T with a sequence similarity of 98.0 %. The polar lipid profile of strain CC65T consisted of phosphatidylglycerol and phosphatidylglycerol phosphate methyl ester. An unidentified glycolipid and two minor phospholipids were also observed. The only quinone present was MK-8(II-H2). The DNA G+C content of strain CC65T was 63.8 mol%. On the basis of the biochemical and physiological characteristics, as well as DNA–DNA hybridization (44 % with Halopenitus persicus IBRC 10041T), strain CC65T is classified as a novel species of the genus Halopenitus , for which the name Halopenitus malekzadehii sp. nov. is proposed. The type strain is CC65T ( = IBRC-M 10418T = KCTC 4045T).